What Can I Expect With New Jets In Carb

[Blackbeard]

Hi All,

I finally tore my carb apart to clean it. I discovered my 2004 RoadStar 1700 had a 37.5 Pilot in it, and I couldn't find any numbers on the Main. I cleaned the carb and put it back on, but the bike still wasn't running as well as it did earlier this summer. Knowing that I needed to pull the carb off again and clean it more, I went ahead and ordered the suggested 40 pilot and the Baron's Jet Kit for the needle and Main. I also ordered a new diaphragm (the old one seemed swollen/ballooned). I'm curious if I should expect any noticeable power-increase, smoother running engine.

I adjusted valves this past summer and changed the plugs while I was at it. The old plugs looked fine with no noticeable sign of it running lean. It always seemed to spit/burp out the intake when it was cold, but that would clear as it warmed up. Is this something that might clear up with the new jets?

The bike is a 2004 1700, pumpless, RoadHouse Dual Exhaust with MaxAir intake.

[Lug Nut]

Did you also do the grizzly needle valve since you went pumpless... What clip position are you using.... Remove the screen fternon carb inlet? Is petcock all clean and free flowing? You keep any inline filter between tank and pump? Vent gas tank cap and/or remove roll over valve?

[Blackbeard]

The conversion was done before I bought it, but I believe all of that is correct. It has a Pingel petcock, a Barons gas cap that I can loosen to vent more. There is not filter between the petcock to the carb (that's why I had to pull it and clean it after I got some trash in it). I don't know about the needle. How would I identify if it's a grizzly? I didn't check the clip position when I cleaned it last as I didn't plan to adjust any of the top of the carb. Sounds like I should set it to the 4th groove from the flat, correct?

I rode it for three years without much of an issue, which is why I believe the pumpless conversion was done properly. I screwed up and ran out of gas on a recent ride and pulled some trash in the carb when I filled the tank. That's when I noticed the jets were different than what folks were saying they should be. It sounded like the 40mm pilot and 172.5 Main was almost standard, but my carb seems like it's jetted for a 1600 instead of a 1700, so I thought I would switch them out. It always seemed to run strong (way more power than my 1998 Honda Shadow Spirit 1100), but I don't know what to expect with the suggested jetting. I'm also going to reseal the manifold and make sure there are no leaks there.

I don't normally play with the carb much, so any advice is greatly appreciated.

[brianmac]

1600s do run strong!

[jd750ace]

A 1700 with 1600 jets would be lean for sure. If you're bumping up the pilot, and you don't have any air leaks, you will likely get less balking or stumble when cracking the throttle open. Should pull a hill better, and should wring 3rd gear out to the rev limiter pretty damn quick (should be in the vicinity of 87 to 90 mph if you have a stock ignition module) Also, it's an 04, so that's the party zone for sticky valve syndrome. Make sure your oil and filter changes, you put in 4 quarts and no more. If I had an 04, I would treat it like my 03, and run 4 ounces of Marvel Mystery Oil in at least every other tank of gas to keep the top end good and clean.

[Blackbeard]

Thanks for the suggestions about the Marvel Mystery Oil. I haven't tried that yet. I pulled the carb apart again today. I can't read the Main Jet too well, but it looks like the current setup is a 37.5 pilot, 180 main and the needle is on the 3rd groove and shimmed with a washer. Here is a pic of the needle in the current configuration. Is this the grizzly needle that you all mentioned previously? I didn't take pics of the jets as I'm planning to follow the 40 pilot, 172.5 main suggestion.

[Brad_G]

The Grizzly needle is for the fuel inlet/float. It's to allow better fuel flow into the carb when the electric pump has been removed.

[Blackbeard]

So, I finished this re-jetting project and thought I would post my initial thoughts in case anyone else had a similar setup that I started with.

Bike Specs:
2004 Road Star 1700 Pumpless
Roadhouse Dual exhaust
MaxAir Intake
Pingel Petcock
No fuel filter
Barons gas cap (can loosen to vent)

The bike was already modified before I bought it, so I didn't know what was in the carb until recently. I just knew it felt like it ran strong and I didn't feel like I needed to mess with it much. The bike always seemed to burp out of the intake, especially when it was cold. The bars would rattle and shake a ton at idle (folks kept asking me if the bike was cammed). It was great in the low end, riding around town, however, the top end felt like it was lacking when I got on the highway. It didn't have any problem getting up to highway speeds, but it just always felt like it should have more range in the top end.

I don't know who the manufacturer was for my initial jets, but the carb had a 37.5 pilot, a 185 main, and a needle that was after-market, but not a Baron's.

I followed the suggestions on here and installed the Barons 40 pilot, 172.5 main and needle (clipped on the 4th groove with a washer, and PMS turned out 2.5 turns. I found a break in the rain yesterday and took it out for a test ride.

It felt like it breathed better, and there was a noticeable change in it's behavior. At idle, the bike didn't shake nearly as badly, the bike didn't burp at idle like it used to, and the throttle response felt smoother through the range. It was great! That was the best that bike has felt in a long time. I'm THRILLED!

I ordered the Grizzly 660 Needle Assembly (which is backordered) and will install that at a later date, but I am thrilled with the throttle response after changing out the jets and needle.

Thanks y'all!

[davej]

I'm glad you are happy with the results. Make sure that after the bike is up to operating temps that the idle is set to around 950 rpm. If you have it set to a low loping idle it could cause the little shake, give an off idle stumble and also lower oil pressure at idle. Might even try a nice heavy dose of seafoam gas treatment in you first tank of gas when you are able to get out for a good ride. It will clean up any heavy carbon deposits on the pistons and valves.

[Blackbeard]

Awesome, will do. I have my idle up. I'll give that a try when I have a longer ride planned. Thanks again.

[davej]

If that needle has 6 grooves in it, it is likely a Speedstar needle. It looks pretty stout in the pic.

[Blackbeard]

I don't think it has 6 grooves, but I'll take another look at it. The taper was definitely different then the Barons.

[atlvfr]

I appreciate the thread. I road last summer with an off idle stumble knowing it was likely due to the need for a larger pilot jet. I knew this because of the knowledge shared on this site. I installed a 40 pilot this afternoon...and no more off idle stumble! The info on RSC was also the deciding factor why I bought my roadstar so many years ago. You guys are the best!